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Prostate androgen receptor: immunohistological localization and mRNA characterization 总被引:1,自引:0,他引:1
Four androgen receptor (AR) specific monoclonal antibodies were used for the immunohistochemical localization of AR in the human prostate tissue. The prostate tissue consisted of alveoli embedded in fibromuscular stroma and lined with a single layer of columnar secretory epithelial cells. The immunoreactive ARs were found predominantly in the nuclei of epithelial cell, suggesting ARs, like estrogen receptors and progesterone receptors, are mainly nuclear proteins. Northern blot hybridization showed that AR mRNA is about 9 kilobases (kb) and relative abundant in the androgen-sensitive organs, such as ventral prostate, dorsolateral prostate and seminal vesicle. 相似文献
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D Liao J J Martin de Llano J P Himanen J M Manning F A Ferrone 《Biophysical journal》1996,70(5):2442-2447
We have developed a photolytic method to determine the concentration of reactive hemes in a solution in the presence of a trace amount of CO. By measurement of the bimolecular rate of CO binding, and by calibration of the rate constant under equivalent conditions, the concentration of the reactive hemes can be determined. In a solution of sickle hemoglobin, the molecules in the gel contribute negligibly to the recombination rate, allowing the concentration of the molecules in the solution phase to be determined. To optimize signal to noise, modulated excitation methods were employed, although the method could also be used with pulse techniques and suitable signal averaging. Because the optical method employs a microspectrophotometer, only a few microliters of concentrated Hb solution is required to reproduce the entire temperature dependence of the solubility previously determined by centrifugation using milliliter quantities of solutions of the same concentration. This should be especially useful for studies of site-directed mutants, and we present results obtained on one such HbS in which Leu 88 beta has been replaced by Ala. The free energy difference in the polymerization of the Leu 88 beta double mutant is consistent with known differences in the amino acid hydrophobicities. The calibration required for these experiments also provides an excellent determination of the activation energy for binding the first CO to deoxy Hb. 相似文献
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Proline uptake can be mediated by three different transport systems in wild-type Salmonella typhimurium: a high-affinity proline transport system encoded by the putP gene and two glycine-betaine transport systems with a low affinity for proline encoded by the proP and proU genes. However, only the PutP permease transports proline well enough t allow growth on proline as a sole carbon or nitrogen source. By selecting for mutations that allow a putP mutant to grow on proline as a sole nitrogen source, we isolated mutants (designated proZ) that appeared to activate a cryptic proline transport system. These mutants enhanced the transport of proline and proline analogs but did not require the function of any of the known proline transport genes. The mutations mapped between 75 and 77.5 min on the S. typhimurium linkage map. Proline transport by the proZ mutants was competitively inhibited by isoleucine and leucine, which suggests that the ProZ phenotype may be due to unusual mutations that alter the substrate specificity of the branched-chain amino acid transport system encoded by the liv genes. 相似文献
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Prostatic ductal system in rats: regional variation in morphological and functional activities 总被引:9,自引:0,他引:9
The rat prostate is a complex ductal system with branches and subbranches extending from one end to another. Owing to the relative distance of various regions of the duct from the urethra, the entire length of the ductal system can be arbitrarily divided into three segments, i.e., the proximal, intermediate, and distal segments. The present study was carried out to assess the regional variation in cellular activities in this ductal system. Ventral prostates from adult Sprague-Dawley rats were dissected so that an individual ductal system was mechanically isolated and longitudinally sectioned to reveal various segments. Epithelial cells lining distal segments were tall-columnar type and were actively engaging in mitotic activity. Cells in intermediate segments were also tall-columnar type. However, they were mitotically quiescent, but able to produce secretory proteins. Evidence of programmed cell death was not observed in either of these two segments. Cells in proximal segments, on the other hand, were low-columnar or cuboidal in shape and were stained heavily for cathepsin D, a marker associated with late manifestation of cell death. Following castration in adult rats, there was a reversal in the site of programmed death in cells lining the ductal system. By Day 4 post-castration, distal segments contained many epithelial cells with intense cytoplasmic staining for cathepsin D while proximal segments showed a reduction in number of positively stained cells. By Day 7 post-castration, cells in proximal segments, though atrophied, were devoid of staining for cathepsin D.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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